Image encoding/decoding method and device, and recording medium in which bitstream is stored

An image encoding method performed by an image encoding apparatus, the image encoding method comprising:

• determining an intra prediction mode of a current block;
• selecting one reference sample line from among a plurality of reference sample lines adjacent to the current block;
• generating reference samples for the current block based on the selected one reference sample line;
• performing intra prediction for the current block using the intra prediction mode and the reference samples;
• and
• encoding the intra prediction mode of the current block using an intra prediction mode of a neighboring block adjacent to the current block,
• wherein the performing intra prediction for the current block comprises,
• selecting an interpolation filter from among a plurality of interpolation filters;
• and
• filtering the reference samples using the selected interpolation filter,
• wherein the interpolation filter is selected based on a size of the current block, and
• wherein the size of the current block is derived based on an average of a log value of width of the current block and a log value of a height of the current block.

A non-transitory computer readable recording medium storing a bitstream that is generated by an image encoding method, the image encoding method comprising:

• determining an intra prediction mode of a current block;
• selecting one reference sample line from among a plurality of reference sample lines adjacent to the current block;
• generating reference samples for the current block based on the selected one reference sample line;
• performing intra prediction for the current block using the intra prediction mode and the reference samples;
• and
• encoding the intra prediction mode of the current block using an intra prediction mode of a neighboring block adjacent to the current block,
• wherein the performing intra prediction for the current block comprises,
• selecting an interpolation filter from among a plurality of interpolation filters;
• and
• filtering the reference samples using the selected interpolation filter,
• wherein the interpolation filter is selected based on a size of the current block, and
• wherein the size of the current block is derived based on an average of a log value of width of the current block and a log value of a height of the current block.